The present invention relates to a light guide plate, a backlight unit and a display device including the same, and more particularly, a light guide plate capable of improving a light diffusion degree, and a backlight unit and a display device including the same.
As a backlight unit (BLU) is one type of light source devices which supply light to the rear surface of a screen of each liquid crystal display (LCD) device, the BLU influences image qualities, such as the luminance of an image, color reproducibility, a viewing angle, a contrast range, legibility, etc., power consumption, a product lifetime, etc., and is a core component which accounts for approximately 20 to 50% of an overall cost of the LCD device.
The BLU is largely classified as a direct-lit type and an edge-lit type according to an arrangement position of a light source. The direct-lit type uses light projected from the light source disposed in the direct rear of a screen light and moved in a direction of a liquid crystal panel, but the edge-lit type supplies light to a display panel by guiding light projected from a light source disposed on an edge of a screen in a side direction to a liquid crystal panel using a light guide plate. Due to a structural difference between the direct-lit type and the edge-lit type, the direct-lit type has advantages for luminance, a contrast range, screen uniformity, image reproducibility, etc., and the edge-lit type has advantages for a product thickness and costs.
Recently, edge-lit type backlights having an advantage of a product exterior have been increasingly important in the display industry because a display product becomes more important for the value of an indoor interior decoration. Particularly, the trend of consumer demands for ultra-thin display products is increasing and studies for reducing diffusion sheets, about 3 to 5 diffusion sheets disposed in the rear of a display panel, as much as possible are actively conducted according to the trend. This type of the display product has problems that a light diffusion degree thereof is difficult to secure as much as that of existing diffusion sheets and a hot spot is issued due to the light diffusion degree. Therefore, the development of a light guide plate capable of improving the light diffusion degree is emerging as a key technology.